Gold of the highlands: a new ground skink (Reptilia: Squamata: Scincidae: Scincella Mittleman, 1950) from southern Vietnam

A new species of ground skink belonging to the genus Scincella is described from high- elevation montane evergreen forests of the Langbian Plateau in southern Vietnam, based on morphological and molecular evidence. Scincella balluca sp. nov. is characterised by a combination of the following characters: (1) slender, medium-sized body, snout-vent length 46.157.9 mm; (2) prefrontals generally separated from each other (rarely in contact); (3) infralabials seven; (4) superciliaries seven (rarely eight); (5) two preoculars, two presuboculars, two postoculars, three postsuboculars; (6) enlarged nuchals absent; (7) supralabials separated from the eye by a row of small scales; (8) tympanum deeply sunk without projecting lobules; (9) midbody scale rows 32 (rarely 30); (10) dorsal scales smooth, slightly enlarged, with paravertebral scale rows 6266; (11) ventral scale rows, including gulars, 6067; (12) upper edge of the dorsolateral longitudinal stripes relatively straight, with six rows of medial dorsal scales; (13) enlarged, undivided lamellae beneath finger IV 1012; (14) enlarged, undivided lamellae beneath toe IV 1820; (15) two enlarged precloacal scales; (16) dorsal surface of body brown with sparsely scattered irregular black spots; (17) ventral surface of throat, belly, and base of tail golden yellow; (18) hemipenes bilobed with two asymmetrical lobes, longer lobe with regular transverse grooves and terminal papillae. Phylogenetic analyses support Scincella balluca sp. nov. as a distinct lineage, with significant mitochondrial divergence from all other sampled Scincella species (uncorrected p-distance > 19.9% in COI, > 5.5% in 16S rRNA). This discovery raises the number of recognised Scincella species to 47. Further taxonomic research and anatomical studies of hemipenial morphology are needed to reassess widespread species complexes within the genus Scincella in Vietnam.